In our herd, we have only one set of full siblings. Chip and Solo are both Honey and Oreo's kids -- but from different years. Chip, a wether (fixed male) has spent nearly his entire life in the buck field. But, I recently moved the two wethers in with the ladies. This was the first time Solo and Chip had met Naturally, the butted heads (literally) and continue to fight like . . . brother and sister. I love how Razz (my no-nonsense gal) attempts to knock some sense into him but then leaves them to their foolishness.
When a new member is introduced to a herd, it's natural to have a little head-knocking as dominance is established, but Chip ONLY picks on poor lil' sis! Oh, well, she seems to enjoy it just a bit. :)